MIPS64: Tweak constants used in seralization process to reflect real state.

src/mips64/assembler-mips64.h

Index: src/mips64/assembler-mips64.h
diff --git a/src/mips64/assembler-mips64.h b/src/mips64/assembler-mips64.h
index 520627a3486422bf8c8ca6de750ed02b2b6cdf8a..1ca1a8714f98c411b97f6073c9fe9db33b36be7a 100644
--- a/src/mips64/assembler-mips64.h
+++ b/src/mips64/assembler-mips64.h
@@ -559,14 +559,11 @@ class Assembler : public AssemblerBase {
   static const int kSpecialTargetSize = 0;
 
   // Number of consecutive instructions used to store 32bit/64bit constant.
-  // Before jump-optimizations, this constant was used in
-  // RelocInfo::target_address_address() function to tell serializer address of
-  // the instruction that follows LUI/ORI instruction pair. Now, with new jump
-  // optimization, where jump-through-register instruction that usually
-  // follows LUI/ORI pair is substituted with J/JAL, this constant equals
-  // to 3 instructions (LUI+ORI+J/JAL/JR/JALR).
-  static const int kInstructionsFor32BitConstant = 3;
-  static const int kInstructionsFor64BitConstant = 5;
+  // This constant was used in RelocInfo::target_address_address() function
+  // to tell serializer address of the instruction that follows
+  // LUI/ORI instruction pair.
+  static const int kInstructionsFor32BitConstant = 2;
+  static const int kInstructionsFor64BitConstant = 4;
 
   // Distance between the instruction referring to the address of the call
   // target and the return address.